Abstract:
A formation evaluating system including a sonic sensor device attached to a drill string adjacent to a bit includes a sonic source and a first sonic receiver aligned adjacent to the sonic source, and a second sonic receiver aligned with a horizontal offset X Three kind of two-way trip times are measured: from the sonic source to a) the first receiver after a reflection at the borehole wall, b) the first receiver after propagation in a layer below the borehole wall, an invaded zone, and a reflection at an interface below the borehole wall, and c) the second receiver after oblique propagations in the invaded zone and a reflection at the interface. After determining a sonic speed in the drilling mud and a sonic speed in a matrix of the invaded zone, a porosity and a thickness of the invaded zone are estimated based on a time average equation.
Abstract:
Aspects of the disclosure provide a system for seismic sample data acquisition and processing. The system includes an acquisition system configured to acquire seismic sample data using compressive sensing. The acquisition system includes a plurality of receivers each configured to randomly sample a seismic signal to generate seismic sample data, and a data collection system configured to control sampling operations of the plurality of receivers, and receive and store the generated seismic sample data.
Abstract:
Methods and an alarming system for long-term carbon dioxide sequestration in a geologic reservoir are described. The geologic reservoir may be a water filled sandstone reservoir or a carbonate reservoir. A reservoir model is constructed to show the effects of varying injection pressures, the number of injection wells, the arrangement of injection wells, the boundary conditions and sizes of the reservoir on caprock uplift, fracture formation and fracture reactivation. The alarming system generates an alarm when caprock uplift that surpasses a threshold is detected. The injection pressures and the number of injection wells operating may be varied in response to the alarm.